Self-traversing drive roll



y 1953 J. J. CALHOUN ETAL: 2,646,227

SELF-TRAVERSING DRIVE ROLL Filed May 9, 1949 INVENTORS JAMES JOSEPH 6ALHOUN8 HARRYM R I A SHALL 000K A TTORNE 1f V Patented July'21, 1953 SELF-TRAVERSING DRIVE ROLL JamesJoseph Calhoun, Waynesboro, and'Harry -Marshall Cook, Staunton, Va., assignors to E. I. du Pont de Nemours '& Company, Wilmington, Del., a corporation of Delaware 1 Application May 9, 1949, Serial No. 92,176 V 8 Claims. (01. 242-42) This invention relates to means for Winding yarn, thread, wire, or similar strand materials into a package on a tube, spool, or similar core and particularly to an improved means for rotating the package and at the same time traversing the thread longitudinally along the package.

It is common practice in the textile industry towind a thread onto a rotating coreand, by

means of a reciprocating guide, to traverse the f thread jalong the rotating core to'form a cylindrical package. this principle produce other shaped packages such 10' Well-known modifications of as cones, tapered packages, etc. In this type of machine, the reciprocating traverse has appre ciable mass and since its direction of motion must be reversed at the end of each stroke, high stresses in the traversing mechanism occur if the reversal takes place at high speeds. This results in vibration and jarring of the mechanism, rapid wear of the moving parts and roughtreatmentof the material being wound. If the reversal is made slower, the thread pilesup on the package at the reversal points and expensive expedients such as secondary motions are required to redistribute the piled-up thread. Consequently, the speed at which such a reciprocating traverse can be operated practically is limited to perhaps 400 cycles per minute or less. Furthermore, when thethread is wound at high speeds with this type of mechanism, it is wrapped onto the core in closely spaced helical coils, forming a so-called parallel wind. It is'desirable tospace the coils farther apart, giving a so-called fcross-wound;

package since this typeof package is more stable in handling and the'yarn willunwind from it more easily, W

. A method of avoiding thedisadvantages of the conventional reciprocating guides comprises the make awinding device which is simple and inexpensive to build and easy to clean and maintain in operation. A ,stillfurther object is the provision of a rapid reversal of the strandat the end of the stroke. Other objects will appear hereinafter.

The objects of this invention are Well accom plished by the use of a rotatable member which has 'an endless groove cut in its outer surface. The groove contains no crossings and is cut helically'in its major portion at an angle of from 5 to 25, with angles varying from 9 to 20 being preferred. This angle in the major portion is designated'for convenience as the normal helix angle. ,Contained in the groove areat least two rapid reversal sections. Each comprises a helicalcut in a minor portion of a groove at an angle which is greater than that of the major portion of the groove. Theangle in the rapid reversal section varies from 15 to'90 withangles approximating. 90 being preferred. In the preferred form the rapid reversal section is rounded and as'such, it follows or is tangent to a helix angle greaterthan the normal helix angle. Usually the helical angle of the major portion ,is about 10 and the helical angle in the minorportion involved in the rapid reversal is about 90. The groove depth is preferably about to 1 /2 inches; the width of the groove varies from to 1 inch, Withwidths of about 'inch being preferred. The width and the depth of the groove are uniform over the length of the groove and all edges are rounded and the surfaces of the groove are treated to prevent abrasion to the strand. The rotatable member surface drives the package onto which the yarn is use of a grooved'traversing roll, In .general, such a roll" consists of a rotating drum having helical groovescut in its surfaceand designed to rotate the-core or yarn package by surface contact therewith. The thread runs in the'groove' and is traversed back and 'forth "along the package as the drum rotates. I reciprocating masses and the device can operate at high speed with reduced vibration and 'Wear. However, the known devices of this sort have serious drawbacks. Relatively high tension on Thus there arefno heavy the threadis required to keep it in the groove and 1 to be .wound, and in its rotation it carries the strand in the groove to the yarn package traversing the strand thereon simultaneously. At the rapid reversal points, the yarn is given an accelerated movement in the direction opposite to which it was being traversed in its approach to the rapid reversal point and this rapid reversal enables the production of properly wound packages. While the depth and the normal helix angle may bevaried as indicated above, the particular value of these factors is chosen so that the quotient of the angle in degrees divided by the depth in inches is'between 5 to 40, with quotients of from 10'to 20 being preferred. Rolls designed with this relationship lead to improved packages because the strand stays in the groove.

Figure 3 is a diagrammatic view, of the yarn win p;

Figure 4 is a sketch of the package formed by the roll of Figure 1 and Figures 5, 6, 7 and 8 are partial developments of the surface of the roll showing variations in curvature of the groove at the point of yarn reversal. V

Referring to Figure 3, the yarn l is led from a supply source through a stationary guide 2 which is located in a plane approximately midway between the two reversal points of the groove, or midway of the distance X-Y, shown in Figure 1. For short strokes this centering is notcritical but for long strokes best results are obtained with proper centering although dead centering is not absolutely essential. The guide is also located so that a yarn wrap-from 45 to 135 around the roll is formed with wraps of 60 to 90 being preferred. From the guide, the thread passes on to the winding drum or drive roll 3 of this invention. This roll runs in contact with the package 4 of yarn being wound. The package 4 is supported by a pivoted arm 5 designed to hold it in surface contact with the rotating drive roll 3. The rotation of the drive roll 3 therefore rotates the package 4 and causes the yarn to wind onto the package. creases in size, shown by dotted lines 5, the arm 5 pivots about its support, still maintaining surface contact with the drive roll. When the package reachesits full size, it is removed; a new core is installed; and the operation is repeated. A core I is shown in Figure 4 bearing yarn 4. 7 As shown in Figure 1, the drive roll 3 has an endless groove 8 cut into its surface. Starting at the reversal poin 9, and proceeding around the roll of Figure 1 in the direction of the'arrow, the groove is cut in the form of a helix with a small helix angle for most of its path to the opposite reversal point In. The normal helix angle continues from reversal point 9 to point II where the helix angle becomes greater in the approach to reversal point I0. Thereafter, the groove continues in the normal helix angle to approach point I2 where the helix angle again becomes greater to reversal point 8. Thus, the last portions of the groove prior to the reversal points are cut with a helix of greater angle than the first portion of the groove.

A rapid reversal section, then comprises a bend in the groove, such as those shown in Figure 1 between the points 9 and I2 and between I!) and H. This bend may involve an angle of from about to 90. Various rapid reversals are shown in Figures 5 to '7. That shown in Figure 5 is designated as a sharp reversal as compared to the rounded reversal of Figure 6. The two lead reversal of Figure 7 is also operable in this invention and differs only slightly from those previously shown.

In operation, the yarn drops into-the groove 8 and as the roll 3 rotates it is traversed along the surface of the package 4 by the edge 13 of the groove until it comes to the reversal point 9. As it passes this point, the thread is momentarily released from the wall I3. The tension, which may be very low, depending on the windup speed, on the thread starts pulling it toward the center of the traverse stroke, which covers approximately the distance from X to Y. This accelerates the return of thread from the edge of the cake. This accelerated reversal reduces the tendency of the yarn to lag or dwell at the ends of the stroke and to pile up in dense layers. Cooperating with the acceleration, the edge [4 of the groove picks up the thread 3 and carries it As the package into the next reversal, where the same action is repeated. Thus, the thread is traversed across the surface of the package by the main helical portion of the groove at a uniform speed until it reaches the end of the stroke, when it is momentarily released by the active edge, briefly ac- "traversed at uniform speed to the next reversal.

For effective sharp reversal, it is preferred that the distance R-S from the reversal point, say 9, to the extension of active edge I4 shown by dotted line I5 in Figures 5 and 6 be at least A; of an inch. If the distance is less, the thread string up and spinning continuity are poor. If greater, there occurs a lag which results in built up shoulders on the package. However, this distance is not limitative, for in other embodiments, such as two lead groove shown in Figure 7, the extended line may intersect or be on either side of the reversal point.

In Figure 8 is shown a reversal which is inoperable unless the shaded area is removed. Such removal in effect, of course, brings the active edge into proper position and the reversal becomes'very much like the rounded reversal of Figure 6. Since grooves of uniform width and depth are preferred such modifications as shown in Figure 8 are not normally used. The rounded reversal of Figure 6 is preferred.

' shown in Figure 8, consisting of minute rounded hills and valleys on all portions of the roll coming in contact with the yarn, and this effect can be obtained by sand blasting, liquid honing which is a wet blasting operation, or etching. It is also desirable that the surface be resistant to wear and corrosion and one way to accomplish this end is to chrome plate it. To illustrate, with a plated roll having a specially prepared pebbly surface only one-third as many yarn defects are obtained as when using, under similar circumstances, a plated smooth surfaced roll.

The grooves, which are, of course, wider than the strand diameters, are preferred to be relatively wide. Widths of A; to 1 inch are preferred to make it easier to string up and to give the contacting edge of the groove a surface treatment to prevent damageto the yarn. The wide groove not only facilitates the cutting, surfacing, and plating of the grooves, but also makes it easier to clean the grooves. Infrequently, a thread breaks and wraps around the roll, instead of on the package. The wide groove permits the removal of the wrap easily by hand or with a tool. If the roll is fixedly attached to its drive shaft, the winding apparatus generally must be stopped to permit cleaning of the grooves or removal of a wrap. This is undesirable when more thanone roll is driven by a common shaft. It has been found that if the bore of the roll 3 is a few thousandths of an inch greater than the diameter of the drive shaft 8, friction between the roll and its shaft will rotate the roll at substantially the same speed as the shaft, but the roll may be stopped by hand or with a brake to permit cleaning while the shaft is still running.

. times necessary to cut a gap in the periphery of the roll to lead the thread intothe groove. Generally, a width of about 4/ inch is preferredfor ease of stringing up, cutting, surfacing, platin and cleaning. The helix angle of the major portion'of the groove, called the normal angle, may vary from 5 to 25, as usually measured withreference to theicircumference of the rotatable member. An angle of 9 to 20 is preferred. The angle of the rapid reversal is greater than the :normal angle and may vary from ;l5 to 90. :Usually, the main groove or :normal angle is 110 and the rapid reversal angle is closeio 190. Ilhe-normal helix angle, the roll diameter, .the stroke and the groove depth are inter-related. For example, the depth ofthe groove may bevaried r a to 1 inchesp'are preferred and employed.

Roll diameter may also'vary, since it is a function of the length of stroke-and depth ,of groove. For example, if it is desired to design a roll for, a 3-inch stroke, and it is decided to use a groove depthof :inch one can easily calculate the diameter. of the roll that should beemployed. Setting .the quotient of the helix angle divided by theidepth equal to 20, one obtains a helix angle of The tangent of 10 being 0.176, half the circumference is equal to 3 inches/.176 or 17 inches and the .diameter is therefore (2x17) 1r or 10.9 inches. Another acceptable combination involves a normal helix-angle of 20,Ia stroke of 3 inches, a diameter of 5 .24: inches and a groove depth of 1 inch. Thus,-theworker can vary the helix angle, depth of groove and diameter of roll over a considerable range, but should hold the ratimof angle over depth to about 20. For a given roll diameter and stroke, .less tension is required to hold the yarn in a deep groove than in shallow groove, and this generally results in less damage to the yarn. However, deep grooves are more diflicult tomake and surface properly, so in practice grooves of from to 'Linch deep seem desirable.

In selecting a roll diameten'it' is desirable to avoid choosing. such-a diameter that the final package will contain a primary ribbon wind, es-

pecially on'its surface. As is well-known in the art, aprimary ribbon wind occurs whenever the number ofcycles .of the traverseper'unit of time is equal to the number of revolutions of the .6 package will not, containzthe primary ribbon. Largeroll diameters arepreferred varying from 5 to 30 inches or more with diameters of about .6 to 12 inchesbeing preferred. There is little advantage in using rotatable members of very large, diameters. However, small diameters, such-as a 3 inch diameter,-,are not useful, because of the difficulty, of obtaining a long enough stroke. This difiiculty cannot'be overcome by using very deep grooves, because'of the diameter limitation; The use of crossed grooves, such as in 'U. S. 1,749,355, overcomes some of the difficulty, but, it is difficult to make such grooves of .uniform depth, and, further, the strand beingtraversed frequently gets in the wrong groove leading. to poor package formation. These and other difficulties, such as primary ribbon winds,

. are avoided by using -the'large diameter rotatablefmembers of this invention;

Eachhalf of the groove is shown extending over the roll circumference, or 180. This-is not "necessary, as more than 180? of rotation could be used for the stroke in one direction and less than 180 for 'the .return stroke. In any case, the total path should add :up to 360 of rotation andthe ratio of helix angle to depth of. groove should be about The yarnis .traversed across the package and back to its starting point once for each revolution of the roll. This is the preferred embodiment. It is obvious that :a larger roll could be designed which would give more than one traverseper revolution and stillxmaintain the ratio of helix angle to groove depth of-about 20. Also rolls are known in which more than one revolution is required for .a complete traverse stroke and in these'rolls the grooves cross each other. Special designs "and complications are required to traverse the "thread .over these crossings "with the result that it :appears impossible to design such a roll with a-groove of uniform depth and sufiicient width throughout 'to permit properrsurfacing of the groove.

In Figurel, a'rollis-shown' with only one "continuous groove around it. It is obvious that the roll could be made :longer andseveral individual grooves-could be cut in its surface. If thesegrooves are cutso that "the ends of their strokes' are *separated from each other, they will wind separatepackages, zone foreach groove, on commen or separate cores. If. they are out so that the ends of their strokes overlap, they would wind interlaced packages such as a beam. Further, it is possible to use a roll having in each groove more than'two rapid reversal sections.

In practice the-grooves usually contain only two rapid reversal sections.

As shown inFigure' l, theedges of the package are slightly'tapered, giving the effect of'a shorter stroke at the 'outside of the package as compared with the core. This effect is produced because there is a shorter lengthof yarn between the roll and the packageat the start than there is when the package is built up to full size. I

It is also apparent that the rotatable member be traversed much more g The .'ro-" tatable members-of -=this invention may be traw erse d very rapidly-1000 cycles per minute or more if necessary thus obtaining excellent package formation "and textile performance.

The rapid reversal or accelerating effect at the end of the stroke reduces the formation of dense layers as hard shoulders on the packages. Moreover, the yarn does not drag over stationary surfaces as the parts of the roll it contacts are moving in the same direction as the yarn and at almost the same speed. These features permit it to handle delicate yarns without damage.

' The use of a relatively wide groove of uniform depth and without crossings permits the easy fabrication of the roll and allows the yarn contacting areas to be carefully made and surfaced so as to protect delicate yarns and this applies if the device of this invention isfabricated from a single roll or from a slotted outer cylinder cooperating with a spaced inner concentric cylinder. The over-all advantages are good cake formation with reduced sensitivity to finish, cake moisture, room humidity, swingarm alignment, etc. Other advantagesare high speed operation, little yarn damage, low maintenance, and reasonable installation cost, all resulting in improved quality, textile performance, and operating cost.

'Any departure from the procedure described herein which conforms to the principles of the invention is intended to be included within the scope of the claims below.

We claim:

'1. A device for traversing a continuous strand on a core comprising a rotatable member provided with means to rotate said member and withan endless groove in its surface helically cu'tin its major portion at an angle of from to 25, said groove containing at least two rapid reversal sections in said groove cut helically at an angle greater than said angle in said major portion and said groove being cut to such a depth that the quotient of said helix angle in the said major portion in degrees divided by the groove depth in' inches is between 5 to 40.

I 2. A'device for traversing a continuous strand on a core comprising a rotatable member provided with -means to rotate said member and with anendless groove in'its surface helically out in its major portion at an angle of from 9 to 20, said groove containing at least two rapid reversal sections in said groove cut helically at an angle greater than said angle in said major portion and said groove being cut to such a depth that the quotient of said angle in said major portion in degrees divided by the groove depth in inches is between 10 to 20.

3. A device for traversing a continuous strand on a' core comprising a rotatable member provided with means to rotate said member and with an endless groove in its surface helically cut in its major portion at an angle of 10", said groove containing at least two rapid reversal sections in said groove out helically at an angle greater than said angle in said major portion and said groove being cut to such a depth that the quotient of said angle in said major portion in degrees divided by the groove depth in inches is about 20.

4. A device for traversing a continuous strand on a core comprising a rotatable member provided-with means to rotate said member and with an endless groove in its surface helically cut in its major portion at an angle of from 5 -tQ--25, said groove containing at least two rapid reversal sections in said groove cut helically at an angle greater than said angle in said major'portion and said groove being cut to such a depth that the quotient of said angle in said major portion in degrees divided by the groove depth in inches is between 5 to 40, said groove having a width of from A to 1 inch.

5. A device for traversing a continuous strand on a core comprising a rotatable member provided with means to rotate said member and with an endless groove in its surface helically cut in its major portion at an angle of from 5 to 25, said groove containing at least two rapid reversal sections in said groove cut helically at an angle greater than said angle in said major portion and said groove being cut to such a depth'that the quotient of said angle in said major portion in degrees divided by the groove depth in inchesis between 5 to 40, said groove having a width of from t 1 inch and being rounded at its upper and lower corners and having a pebbly surface.

6. A'device for traversing a continuous strand on a core comprising a rotatable member provided with means to rotate said member and with an endless groove in its surface helically cut in its major portion at an angle of from 5 to 25 and at a depth of from to 2 inches and awidth of from A; to 1 inch, said groove containing at least two rapid reversal sections comprising cuts in the said groove which cuts are made in a minor portion of the said groove at an angle greater than said angle in said major portion and having a value of from 15 to the said rotatable member having a diameter of from 5 to 30 inches.

7. A device for traversing a continuous strand on a core comprising a rotatable member provided with means to rotate said member and with an endless groove in its surface helically cutin its major portion at an angle of from'9 to 20 and at a depth of from to 1 inches and a width of from to 1 inch, said groove containing at least two rapid reversal sections comprising cuts in the said groove which cuts are made in a minor portion of the said groove at an angle greater than said angle in said major portion and having a value of from 15 to 90, the said rotatable member having a diameter of from 6 to 12 inches.

8. Adevice for traversing a continuous strand on a core comprising a rotatable member provided with means to rotate said member and with an endless groove in its surface helically cut in its major portion at an angle of 10 and at a depth of inch and a width of inch said groove containing two rapid, rounded reversal sections comprising cuts in the said groove which cuts are made in a minor portion of the said groove at an angle of about 90, said rotatable member having a diameter of 77 inches.

JAMES JOSEPH CALHOUN. HARRY MARSHALL COOK.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 868,013 Rivett Oct. 15, 1907 1,161,284 Belz Nov. 23, 1915 1,727,884 Jessen Sept. 10, 1929 1,918,210 McKean July 11, 1933 1,928,365 Anderson Sept. 26, 1933 1,975,037 Durand Sept. 25, 193% 1,980,113 Taylor Nov. 6, 1934 2,151,327 Moncreif Mar. 21, 1939 2,249,147 Kuppers July 15, 1941 

